A Comparison between All Share Price Index and Standard and Poor’s Sri Lanka 20 Index

Abstract

This research studies the daily returns of the two main indices in Colombo Stock Exchange; namely the Standard and Poor’s Sri Lanka 20 and All Share Price Index, to examine the nature of their return distribution and volatility. The main objective of the paper is to investigate whether any one index outperforms the other in terms of its returns and volatility. Data is collected for a sample period of 12 months and analyzed using the SPSS statistical software. A normality test was carried out to explore the nature of return distribution and it is found that the return distribution of both ASPI and S&P SL 20 index are not normally distributed. Positive value of skewness and kurtosis of the two indices further reinforces this fact. Levene’s test shows there is no statistical difference in variance of indices. Further the independent sample t test and Mann-Whitney U test infer that there is no statistically significant difference between the mean returns of the two indices. Nevertheless the results of the return per unit of risk show that ASPI reports a higher return per unit of risk compared to S&P 20.